Eucommiidites

Eucommiidites is an angiosperm look-alike pollen type from the Mesozoic Era. When it was first described in Sweden, it was thought to represent pollen from the earliest angiosperms.[1] However, it was subsequently shown, due to morphology, that it could not be angiospermous.[2] Later, Eucommidites pollen was discovered in the pollen chambers of fossil gymnosperm seeds. It was later shown to be the pollen of the extinct gymnosperm order Erdtmanithecales, suggested to have close affinities with Bennettitales and Gnetales.

Eucommiidites
Temporal range:
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Order: †Erdtmanithecales
Genus: †Eucommiidites
Erdtman 1948
Species
  • †Eucommiidites minor
  • †Eucommiidites stuartii
  • †Eucommiidites troedssonii

Eucommidites is tricolpate, which is why it was originally thought to be angiospermous. However, the three colpi are not equal in length, and the exine of the pollen grain is similar to a gymnosperm.

Eucommidites is important in biostratigraphy, and it ranges from the Triassic to the Cretaceous.[3]

References
  1. G., Erdtman. Suggestions for the classification of Fossil and recent Pollen grains and spores. OCLC 79753642.
  2. Couper, R. A. (May 1956). "Evidence of a possible gymnospermous affinity for Tricolpites troedssonii Erdtman". New Phytologist. 55 (2): 280–285. doi:10.1111/j.1469-8137.1956.tb05286.x. ISSN 0028-646X.
  3. Traverse, Alfred (1988). Paleopalynology. Unwin Hyman. ISBN 978-0045610013. OCLC 17674795.


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